The present invention relates to a bar type temple for a weaving machine.
Bar type temples of the named kind are known from practice as constituents of weaving machines. The purpose of the bar type temple in the weaving machine consists in holding the cloth web manufactured in the weaving machine constant against the forces arising when shooting in weft threads transverse to the warp thread direction. For this the already woven cloth web is in each case clamped at a slight distance from the weft insertion during the shooting in. This clamping is done through a drawing tension under which the warp threads and already woven cloth web are held. Through this drawing tension the cloth web is pressed along two lines against a lower edge and an upper edge of the longitudinal slit in the bar carrier, through which the web is sufficiently firmly clamped in and thus held at its desired width. Since, however, the web must in addition be gradually transported further to the cloth beam in accordance with the progress of the weaving, the clamping must be briefly loosened between two successive shootings in of the weft thread. This loosening of the clamping is done by the beating up of the just shot in weft thread against the end of the already woven web, through which the drawing tension in the web between the beatup and the cloth beam briefly decreases to such an extent that the clamping is decreased in a measure sufficient for a further transport of the web by a distance corresponding to the weft thread thickness.
The above described bar type temple with a single working bar operates thoroughly satisfactorily in dense-weft cloth, i.e. in the manufacture of fabrics with a relatively large number of weft threads per unit length. Problems result, however, when weaving medium-weft and light-weft fabrics, i.e. cloths with low or very low numbers of weft threads per unit length. For low-weft ware in particular situations arise in which the bar jams and an undesirably high drawing tension thereby builds up in the web, which can lead to damage or a lowering of the quality of the cloth. In addition the high tension in the web can lead to loose places in the cloth, with breaks in the warp and weft threads which can no longer be eliminated through subsequent corrections. Furthermore, it can be observed in practice that yarn residues often get wound around the working bar and then lead to visible pressure points in the finished cloth which represent a lowering of the quality. In addition, the irregular running of the bar caused hereby results in periodically arising loose and tight places occurring in the cloth, which is known as the so-called "washboard effect".